We will complete the mapping of the routes of carbohydrate metabolism in Entamoeba histolytica. Prior studies have already disclosed some highly unusual features in this metabolism between P-enolpyruvate and pyruvate, and at the step producing the alcohol end product. Remaining to be explored are the processes of glycogen synthesis, the production of the acetate, the production of hydrogen and the significance of the enzyme system cleaving phosphogluconate to pyruvate and triose-P. We will employ isotope tracers to mark the pathways functioning in resting cells and in growing axenic ameba. Biochemical methods will then be employed to isolate and characterize the enzymes responsible for these processes. We will seek differences between the pathogenic strains of ameba and the non-pathogenic strains which may shed light upon the reasons for pathogenicity. Differences between parasite metabolism and that of the human host will be investigated in order to provide background information which may later be useful in mounting a pharmacological attack upon the parasite at those sites where its metabolism is most susceptible to the action of specific blocking agents.